The field of mixing paints and other liquids is aimed at employing some form of agitating mechanism for stirring and mixing liquids containing solids so as to hold such solids evenly and uniformly distributed in suspension within the liquid. Agitation is necessary when dealing with the long term storage of such things as paints, varnishes, stains, shellac, enamels, and the like which are an emulsion of, among other things, fine solid particles, binders composed of oil or resin, thinners and organic or water solvents which, if left unperturbed for an extended period of time, the heavier solids and components, having higher densities in the emulsion, would soon begin to settle at the bottom of any container in which they are left.
When paint or other liquid jet is left to settle, the dense solid components and heavier liquids can become a thick mud-like sludge at the bottom of the storage container. Such effect is commonly found with commercial paint and varnish products which, in order to prepare the emulsion for its intended purpose, require a considerable amount of stirring to evenly redistribute and suspend the solids within the liquid component before application. In short term mixing prior to use, such method to re-suspend the mixture with smaller quart, pint, and gallon containers presents some time and effort but remains manageable.
Yet, in the larger long term storage tanks holding countless gallons of the emulsion prior to its distribution within smaller containers, such sludge can build up to an unmanageable degree. In less serious cases the storage container may require considerable time and money to break up the sludge and re-suspend the emulsion evenly. In the more serious circumstances the entire emulsion may be required to be discarded due to the buildup, sometimes damaging the storage container or even necessitating the scrapping of the storage container itself. Consequently, it is preferable to constantly or periodically agitating the emulsion so as to prevent the buildup of sludge in the tanks.
Due to the extreme size of the storage tanks and the massive volume of fluid contained therein, a number of mechanical devices are utilized for facilitating the agitation of tanks without the necessity of having a worker enter the tank. Such devices employ large articulating paddles or rotary blade impellers positioned at the top or the sides of the tanks to impart stirring to the emulsion. These devices typically employ rotaries or gimbals mounted to the side of the tank to allow for the rotation of the agitators within the emulsion. When positioned from the top, such devices cause fluid, and suspended solids, to be projected at high velocities down against the tank floor which can cause ear on the tank integrity and drive the heavy solids to the bottom, creating sludge. When positioned from the sides, such devices fail to sufficiently circulate the fluid at the tank floor which typically has a slight downward slope towards its center, thus leaving a substantial portion of the tank undisturbed where sludge can form. As well, agitators designed to be rotated within the tank can become stuck in settled sludge or locked up by sludge which has been disengaged from the tank floor wherein the paddle or rotary blade will no longer be allowed to rotate.
Methods of mixing other fluids containing particulate matter such as in the fields of tank cleaning, waste management, and separating oil-water emulsions employ jet nozzles in order to produce high velocities of fluids into tanks in order to scour the inside of the tank or mix the contained emulsion with treated fluids, such as water of detergent. Though, such methods are not conducive to that of mixing paints, varnishes, stains, shellac, enamels, and the like which must be maintained in their present mixture of components. Addition of external fluids into the tank would dilute the contained mixture, ruining the product. Further, recirculation of the contained fluid mixture is unfavorable as the tank emulsion contains solids and heavier density fluids. Attempting to drive mixing through recirculation, wherein the contained fluid and solids are suctioned into and pumped out of a recirculating device, clogs up the nozzles, pipes, and pumps of the recirculating device causing breakages and failures to properly mix.
A need exists for a simple, user controlled propulsion recirculation device that may be deployed within the interior of an above ground storage tank to maintain suspension of solids and heavy liquids within the mixture.